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The Effect of Nitrogen Gas Cooling Which Is Used in Aluminium Extrusion Mold on Production Efficiency 被引量:1
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作者 Merve Ozcan Cemal Ozsut +1 位作者 Oguzhan Deveci Gulbahar Bentesen 《Open Journal of Applied Sciences》 2021年第4期414-421,共8页
It is aimed to investigate the efficiency of nitrogen gas cooling which is used in aluminium extrusion mold in this study. The exit temperature of extrusion profile increases depending on heat generated by friction an... It is aimed to investigate the efficiency of nitrogen gas cooling which is used in aluminium extrusion mold in this study. The exit temperature of extrusion profile increases depending on heat generated by friction and forming. This situation can cause to surface defects such as hot cracks and grain thickening after extrusion process. Cooling of the mold has a critical role in terms of dissipating heat close to the forming zone. Local internal cooling experiments were performed in the hot aluminium extrusion mold within the scope of this study. It has been obtained that exit temperature of the aluminium extrusion profile can be significantly reduced in experimental results. Also it was found that the reduction of press time (s) and increase of press speed (mm/s). This paper focuses the effect of nitrogen gas cooling on extrusion mold for process efficiency. The extrusion parameters were performed for comparative analysis. Its obtained that process ensures efficiency. 展开更多
关键词 Aluminium Extrusion Mold Cooling System production efficiency
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Measurement of Grain Production Efficiency in Main Grain-producing Areas and Analysis of Inter-provincial Differences--A Study Based on Super-SBM Model and Malmquist Index
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作者 Qi Heng Su Jing-yan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第2期86-96,共11页
China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-p... China's food security mainly depends on the core areas of food production.Under the dual constraints of resource scarcity and environmental degradation,improving the grain production efficiency of the main grain-producing areas has become the fundamental way to strengthen the grain production capacity and improve the national food security capability,and to improve the efficiency of grain production in major grain-producing areas requires empirical support.This paper used the Super SBM model and the Malmquist index to measure the grain production efficiency of the main grain-producing areas from 2001 to 2020 from both static and dynamic perspectives,and compared the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas.The results showed that from 2001 to 2020,the grain production in the main grain-producing areas was in a relatively ineffective state,and the differences in grain production efficiency among different soil types and different provinces(autonomous regions)in the main grain-producing areas were obvious.The order of grain production efficiency in different soil types was black soil region>red-yellow soil region>paddy soil region>fluvo-aquic soil region,and the order of grain production efficiency of the provinces(autonomous regions)in the main grain-producing areas was Jilin>Heilongjiang>Inner Mongolia>Jiangxi>Hunan>Sichuan>Hubei>Jiangsu>Liaoning>Henan>Anhui>Shandong>Hebei.From 2001 to 2020,the total factor productivity of grain in the main grain-producing areas increased,but due to the trade-off between the technological progress and the growth of technical efficiency,the increase in the total factor productivity of grain in the main grain-producing areas was small,and the growth mainly came from the increase of input factors in this period.The total factor productivity of grain in Hebei,Heilongjiang,Liaoning,Jilin,Inner Mongolia,Shandong,Jiangsu,Henan and Anhui increased,but the increase was small,while the total factor productivity of grain in Jiangxi,Sichuan,Hunan and Hubei provinces declined. 展开更多
关键词 main grain-producing area grain production efficiency inter-provincial difference
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Calculation of Agricultural Production Efficiency Based on a Three-stage Data Envelopment Analysis Model and Analysis of the Spatial-temporal Characteristics: A Case Study of the Yangtze River Economic Belt
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作者 Wenjun ZHUO Haiyang CUI 《Meteorological and Environmental Research》 CAS 2021年第5期68-76,83,共10页
In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,th... In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,the Yangtze River Economic Belt is adjusting the agricultural industry structure,optimizing the input-output ratio,and ensuring stable and sustainable agricultural production. Based on the combination of the three-stage Data Envelopment Analysis( DEA) model and cluster analysis,this study examined the Yangtze River Economic Belt from 2008 to 2018 to measure its agricultural production efficiency and to analyze its temporal and spatial characteristics. Studies showed that exogenous environmental factors significantly( P < 5%) impacted agricultural production efficiency in the Yangtze River Economic Zone,and there were temporal and spatial differences. These included:(1) after excluding environmental factors,the overall agricultural production efficiency of the Yangtze River Economic Zone had improved. Sichuan Province and Jiangsu Province were at the forefront of efficiency,whereas the agricultural production efficiency of Shanghai had declined obviously.(2) The agricultural production efficiency of the Yangtze River Economic Belt varied year by year,with fluctuating development. The middle reaches of the Yangtze River had advanced agricultural production efficiency more than the upstream and downstream regions,and the agricultural production efficiency of the individual provinces did not match their economic and social development.(3) Increases in labor,land,irrigation,and other input factors increased agriculture production efficiency,and there was no correlation between fiscal investment,per capita gross domestic product( GDP) and agricultural production efficiency,while the disaster-affected area had a significantly negative impact on agricultural production efficiency. 展开更多
关键词 Agricultural production efficiency Three-stage Date Envelopment Analysis Temporal and spatial characteristics Yangtze River Economic Belt
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Does Security of Land Operational Rights Matter for the Improvement of Agricultural Production Efficiency under the Collective Ownership in China? 被引量:2
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作者 Xianqing Ji Shouying Liu +1 位作者 Jianan Yan Youyi Li 《China & World Economy》 SCIE 2021年第1期87-108,共22页
Under the"separation of three rights"policy,the impact of security of land operationalrights on agricultural production efficiency has attracted much attention in recentyears.Data envelopment analysis and me... Under the"separation of three rights"policy,the impact of security of land operationalrights on agricultural production efficiency has attracted much attention in recentyears.Data envelopment analysis and mediation effect analysis were applied to 888family farms run by new-type agricultural operators from Songjiang to identify themechanism of the effect of land operational rights security on agricultural productionefficiency through long-term investment.The results show that greater security of landoperational rights generally increased agricultural production efficiency.Approximately37.94 percent of the impact could be explained by long-term investment.The resultsalso indicate that significant heterogeneity exists in the effect of land operational rightssecurity on agricultural production efficiency at various levels of the family farms'efficiency distributions.lt is suggested that government should legalize land operationalrights and give them a status equal to those of households'contractual rights and landownership rights in China's future land tenure reform. 展开更多
关键词 agricultural production efficiency new-type agricultural operator security of land operational rights
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Spatial differentiation and evolution trend of technical efficiency of forestry production in china
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作者 Xu Yang 《Proceedings of Business and Economic Studies》 2021年第1期1-5,共5页
Based on the non-radial super-efficiency SBM model,the technical efficiency of forestry production in 30 provinces(municipalities,autonomous regions)across the country was measured from 2004 to 2018,and the Makov chai... Based on the non-radial super-efficiency SBM model,the technical efficiency of forestry production in 30 provinces(municipalities,autonomous regions)across the country was measured from 2004 to 2018,and the Makov chain was introduced to analyze the evolution trend.The research found that:The average PTE of China's forestry from 2004 to 2018 was 0.516,and the overall level was not high;regional imbalances were prominent,showing a distribution pattern of"high in the south and low in the north"and"high in the east and low in the west".Regions with low and high levels of Forestry PTE have certain characteristics of"path dependence".in the long run,Forestry PTE growth will face greater pressure. 展开更多
关键词 FORESTRY production technology efficiency Makov chain
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Practical Analysis of Mechanical Automation Technology in Automobile Manufacturing
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作者 Miao Zhang 《Journal of Electronic Research and Application》 2023年第5期24-29,共6页
In today’s rapidly developing modern society,automobiles,as an important part of transportation and industrial fields,play a pivotal role.With the improvement of people’s living standards and the increase in traffic... In today’s rapidly developing modern society,automobiles,as an important part of transportation and industrial fields,play a pivotal role.With the improvement of people’s living standards and the increase in traffic demand,the automobile manufacturing industry has been continuously developing and growing globally.However,to cope with increasingly fierce market competition and ever-changing consumer demands,the automobile manufacturing industry is also facing the challenges of improving production efficiency,reducing costs,and improving product quality.In this context,automation technology has gradually become a major trend in the automobile manufacturing industry.As an important support of modern industry,automation technology has shown great application potential in many fields.From industrial production to daily life,automation technology can be seen everywhere.In the field of manufacturing,especially in automobile manufacturing,the application of automation technology is getting more and more attention.Automated production lines,intelligent robots,and automated warehousing systems have all changed the face of automobile manufacturing to varying degrees,bringing companies higher efficiency,more stable quality,and greater competitive advantages.The application trend of this automation technology in various fields not only meets the needs of modern industry for efficient,precise,and sustainable development but also provides new ideas and paths for the future development of the automobile manufacturing industry. 展开更多
关键词 Mechanical automation technology Automobile manufacturing Practical analysis production efficiency
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Functions of Nitrogen,Phosphorus and Potassium in Energy Status and Their Influences on Rice Growth and Development
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作者 MA Jiaying CHEN Tingting +8 位作者 LIN Jie FU Weimeng FENG Baohua LI Guangyan LI Hubo LI Juncai WU Zhihai TAO Longxing FU Guanfu 《Rice science》 SCIE CSCD 2022年第2期166-178,共13页
Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamb... Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamber for 20 d at 30℃/24℃day/night)under natural sunlight conditions with different nutrient regimes.The results showed that N had the strongest influence on the plant growth and development,followed by P and K.The highest nonstructural carbohydrate content,dry matter weight,net photosynthetic rate(Pn),ATP content,as well as NADH dehydrogenase,cytochrome oxidase and ATPase activities were found in the plants that received sufficient N,P and K.The lowest values of these parameters were detected in the N-deficient plants.Higher dry matter accumulation was observed in the K-deficient than in the P-deficient treatments,but there was no significant difference in the ratio of respiration rate to Pn between these two treatments,suggesting that differences in energy production efficiency may have accounted for this result.This hypothesis was confirmed by higher ATP contents and activities of NADH dehydrogenase,cytochrome oxidase and ATPase in the K-deficient plants than in the P-deficient plants.We therefore inferred different abilities in energy production efficiency among N,P and K in rice seedlings,which determined rice plant growth and development. 展开更多
关键词 RICE nutrient element PHOTOSYNTHESIS RESPIRATION plant growth and development energy production efficiency
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Learning Effect and Productivity Convergence of Chinese Industrial Enterprises
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作者 Tinghua Liu Jingru Wang Xiao Liu 《Journal of Finance Research》 2020年第2期92-105,共14页
The main purpose of this paper is to test the production efficiency of different Chinese property industrial enterprises.Based on the large sample panel data of industrial enterprises of the National Bureau of Statist... The main purpose of this paper is to test the production efficiency of different Chinese property industrial enterprises.Based on the large sample panel data of industrial enterprises of the National Bureau of Statistics,we found that although the production efficiency of China-funded enterprises is generally weaker than foreign-funded enterprises,some China-funded enterprises have better learning ability.On the one hand,dynamic analysis found that private enterprises have significant learning ability.On the other hand,the results of convergence analysis show that China’s private enterprises have the potential to gradually catch up with the frontier level of world production efficiency and have better learning ability to catch up potential.And state-owned enterprises tend to be more efficient at the beginning of their establishment,but their productivity is fairly slow to improve,especially for state-owned enterprises with high efficiency sub-samples,so that it’s hard for them to continue improving their efficiency.Institutional analysis found that the marketization process helped the China enterprises to improve their learning ability and China should continue to strengthen the reform of property rights and promote the marketization process. 展开更多
关键词 production efficiency Learning effect efficiency catch-up βconvergence analysis
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A data envelopment analysis of agricultural technical efficiency of Northwest Arid Areas in China 被引量:3
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作者 Yubao WANG Lijie SHI +1 位作者 Haojie ZHANG Shikun SUN 《Frontiers of Agricultural Science and Engineering》 2017年第2期195-207,共13页
Severe resource shortage and waste of resource in agricultural production make it necessary to assess efficiency to increase productivity with high efficiency and ensure sustainable agricultural development. This pape... Severe resource shortage and waste of resource in agricultural production make it necessary to assess efficiency to increase productivity with high efficiency and ensure sustainable agricultural development. This paper adopted an input-oriented data envelopment analysis(DEA) method with the assumption of variable returns to scale to evaluate agricultural production efficiency of 100 major irrigation districts in Northwest China in 2010.Major findings of this paper were as follows: firstly, the average value of total technical efficiency, pure technical efficiency and scale efficiency of those irrigation districts in Northwest China were 0.770, 0.825 and 0.931,respectively; secondly, 30% of irrigation districts were technically efficient, while 42% and 32% of them showed pure technical and scale efficiency respectively. Among inefficient decision-making units, total technical efficiency score varied from 0.313 to 0.966, showing significant geographical differences, but geographical differences of pure technical efficiency was more consistent with that of total technical efficiency; thirdly, input redundancy was evident. Inputs of agricultural population, irrigation area,green water, blue water, consumption of fertilizer and agricultural machinery could be reduced by 34.88%,40.19%, 43.85%, 47.10%, 41.53% and 42.21% respectively without reducing agricultural outputs. Furthermore,irrigation area, green water and blue water had relatively high slack movement though Northwest China which is short of water resources. Based on these results, this paper drew the following conclusions: First, there is huge potential for Northwest China to improve its agricultural production efficiency, and agro-technology not input scale had greater influence on improvement. Second, farmers needed proper guidance in order to reduce agricultural inputs and it is time to centralize agricultural management for overall agricultural inputs regulation and control. 展开更多
关键词 agricultural production efficiency DEA model input redundancy irrigation districts Northwest Arid Areas in China
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An approach to optimize the batch mixing process for improving the quality consistency of the products made from traditional Chinese medicines 被引量:2
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作者 Bin-jun YAN Hai-bin QU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第11期1041-1048,共8页
The efficacy of traditional Chinese medicine(TCM)is based on the combined effects of its constituents.Variation in chemical composition between batches of TCM has always been the deterring factor in achieving consiste... The efficacy of traditional Chinese medicine(TCM)is based on the combined effects of its constituents.Variation in chemical composition between batches of TCM has always been the deterring factor in achieving consistency in efficacy.The batch mixing process can significantly reduce the batch-to-batch quality variation in TCM extracts by mixing them in a well-designed proportion.However,reducing the quality variation without sacrificing too much of the production efficiency is one of the challenges.Accordingly,an innovative and practical batch mixing method aimed at providing acceptable efficiency for industrial production of TCM products is proposed in this work,which uses a minimum number of batches of extracts to meet the content limits.The important factors affecting the utilization ratio of the extracts(URE)were studied by simulations.The results have shown that URE was affected by the correlation between the contents of constituents,and URE decreased with the increase in the number of targets and the relative standard deviations of the contents.URE could be increased by increasing the number of storage tanks.The results have provided a reference for designing the batch mixing process.The proposed method has possible application value in reducing the quality variation in TCM and providing acceptable production efficiency simultaneously. 展开更多
关键词 Batch-to-batch quality consistency Batch mixing production efficiency Traditional Chinese medicine
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Efficient and collective total synthesis of natural products via radical cascade reactions
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《Science Foundation in China》 CAS 2017年第3期32-32,共1页
Subject Code:B02With the support of the National Natural Science Foundation of China,the research team led by Prof.Qin Yong(秦勇)at Sichuan University accomplished a collective synthesis of 33 monoterpenoid indole alk... Subject Code:B02With the support of the National Natural Science Foundation of China,the research team led by Prof.Qin Yong(秦勇)at Sichuan University accomplished a collective synthesis of 33 monoterpenoid indole alkaloids that belong to four families,by developing new photoredox-initiated radical cascade reactions. 展开更多
关键词 Efficient and collective total synthesis of natural products via radical cascade reactions FIGURE
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